Expanding chuck



Sept. 15,` 1959 H. EWING EXPANDING CHUCK 2 Sheets-Sheet 1 Filed Feb. 6, 1957 sept. 15, 1959 L. H. EwlNG rEXMNDING CHUCK 2 Sheets-Sheet 2 Filed Feb. e, 1957 EXPANDING CHUCK Lynn HK. Ewing, Rock Island, Ill. Application February v6, 1957, Serial No. 638,638 6 claims. (ciau-71.1)l

The present invention relates to expanding vchucks and more particularly'to expanding chucks for supporting a roll of paper or other like sheet material on a shaft.4

One object of the present invention is to provide an expanding chuck which, when mounted on a shaft and inserted in the core of a paper roll, is easily expanded or collapsed and, when in the expanded position, affords a secure, positive and uniform gripping-action onboth the shaft and the core.

Another object of the present invention is -to adapt conventional paper roll ychucks for use with paper roll cores of large internal diameter'while maintaining perfect centering and uniform expansion of the chuck within such a core.

A further object of the present invention is to increase the A'gripping action between variable ,size expandable paper roll chucks having the above characteristics and fa'holl'ow core in order to achieve a positive, driving connection there-between and to prevent the slipping or coasting o'f the roll under conditions of high lbrake tension.

Other objects and advantages of the present invention will become apparent as the following description proceeds, taken in connection withrthe accompanying drawings wherein:

Figure 1 isa perspective View of a paper roll mounted on a shaft by a'pa'ir of chucks and adaptors illustrative by the present invention. y

Fig. 2 is a longitudinal elevation view, partly in section, of the right end chuck and adaptor shown in Fig. 1, the View being taken generally on the line '2 2 of Fig. 4.

Fig. 3 is a transverse section taken substantially in the plane of line 3-3 of Fig. 2.

Fig. 4vis a transverse section taken substantially in the plane of line 4 4 of Fig. 2.

Fig. 5 is a perspective View of an expandable chuck leaf of the type used in the chuck shown in Fig. l.

Fig. 6 isa 'perspective View of an adaptor chuck leaf for use with the chuck collar shownin Fig. 5 and illustrative of the present invention.

While the invention is susceptible of Various modifications and alternative constructions, a certain illustrative chuck has been shown in the drawings and will be described below in detail. lt should be understood that there is no intention to limit the invention 'to the form disclosed. On the contrary, the intention Vis to cover all modificationnalternative constructions and equivalents falling within the spirit and scope of the invention as expressed in the .appended claims.

In order to secure a `core mounted paper roll 10 on a shaft 11 as shown in Fig. 1a pair of expansible .adapter chucks 12 are mounted on the shaft and are inserted into the. respective ends of the core 13 of the rolllt). By expanding the chucks to engage the inner area of the core and by tightening them onithe shaft, the Vpaper roll and shaft are securely gripped and held in a non-rotative relation. While one of the pair. yof chucks will be described,

ice

it will be vunderstood that the other is similar in all respects.

One illustrative example of an expanding chuck 1 ;2 (Fig. 2) suitable for securely mounting a paper roll 10 on a shaft 11 comprises an inner cam member 15 in the form of an annular cylinder adapted to ybe placed around the shaft and secured thereto by means of a clamping bolt 16. The inner member 15 carries on its outer surface an undulating cam face 17 formed of an axial succession off transverse ridges `17a and valleys 17 b. l

A plurality of axially extending quadrant-shaped segmental leaves 20 are circumferentially spaced around the inner member 15. Each leaf 2l) has on its inner surface an undulating cam face 2.1 of a form similar yto the cam face 17 on the inner member 15 `(Fig. 2) `and Van outer arcuate surface 51. When the leaves 20 are placed around the inner member 15 the ridges formed by ythe undulating cam face on one nest within the valleys formed by the undulating cam face on the other so that the cam faces 17 and 21 are mutually engaged. lOne or more coil springs 24 serve to hold the leaves in place on the inner member forming generally on the outer faces 51 a circular bearing surface.

To increase the outer circumference of the circular vbearing surface of the nested leaves they are moved axially along the inner member, the cam action between the undulating faces 17 and 21 on the leaves 20 and the inner member 15 forcing the leaves radially outwardly to a larger external diameter. The axial movement giving the cam action is accomplished by a nut 25 threadably mounted on theinner member y15 and having an annular shoulder 26 which engages an annular collar 2,7 on the ends of the leaves 2l).

When the nut is rotated, a force is exerted between the shoulder 26 and the collar 27. This axial force is transmitted to the engaging cam surfaces 17 and 21 forcing the leaves to be expanded on the inner member. For example, when the chuck is inserted in a core 13 the leaves upon expansion engage the inner surface of the core and if sufficient force is exerted on the nut, the chuck is tightly engaged therewith.

A Spanner wrench is desirably, although not exclusively employed for rotating the nut on the inner member. To this end a series of holes 28 are circumferentially disposed around the nut for engagement by the Spanner wrench.

In accordance with the present invention, provision is made for increasing the outer circumference of a paper roll holding chuck in order to accommodate it for use with paper roll cores having large inner diameters. This is accomplished by the yuse of `a plurality of annular 4or quadrant-shaped adapter chuck leaves 30 fastened over the chuck leaves 2G to increase the radial thickness thereof. 4One of the annular adapter chuck leaves 30 is nested 'around each of the chuck leaves 20 and in effect increases the thickness of each of them. Each -adapterleaf 30 is alined with a corresponding leaf 20 and the outer circumference of the chuck is tb-us increased to slightly smaller than the circumference 0f the oversize core 13. Upon expansion of the chuck, the outer surfaces of the supplementary chuck leaves 30 positively engage ythe inner Surface of the paper roll core.

In order to increase the gripping action and at the same time reduce the weight of the adapter chuck leaves 3l), each is formed with two outwardly flaring radial slotsv 31 which form three radial Walls 32. The outer edges of these walls, when the adapter is in use on the chuck, bite into the yieldable surface of the paper roll core and firmly anchor it with respect to the chuck. In this respect, the paper roll core surface, being relatively soft compared to the walls of the adapter leaves 30, is deformed to project slightly within the slots 31, thereby in;

members 30 from rotating relative to the chuck leaf members 20. To this end, one of the chuck leaves 20 (Fig. 5) is formed with two axially extending spacedkeys 34. These keys project into the radial slot-s 31 of one. segmental core member and engage the radial walls thereof when it is placed on that leaf. The leaves 20 are in turn prevented from rotating relative to the inner member 15 by an axially extending key 35 on the latter which projects radially and longitudinally between two of the leaves 20. Relative rotation between the leaf members of the chuck and the inner member 15 is thus seen to be effectively precluded.

The chuck assembly 12 is prevented from sliding within the large diameter core of the paper roll by an annular shoulder 37 on one end of each of the adapter leaf members 30. This collar formed by shoulders 37 engages the end of the core 13 to position the chuck 12 therein. The adapter leaf members 30 are held in surrounding relation on the chuck leaves 20 by means of coil springs 38 which lie in grooves 39 on the adapter leaf members 30.

To mount a roll of paper 10 having a large diameter core 13 on a shaft 11, the inner member 15 of a chuck 12 of the type described above is secured onto the shaft 11. The separate chuck leaves 20 are held on this inner member with the cam faces of each in mutual engagement by the coil spring 24 and the tightening nut 25. The adapter leaf members 30 are then placed around the chuck leaves 20 and held thereon by the coiled springs 38. The shaft is then inserted through the core of the roll and a second chuck is then secured on the shaft with one end engaged within the core. A spanner wrench or the like is engaged with the nuts on both of the chucks which are rotated to expand the leaves against the tension exerted by the coil springs ,and into engagement with the inner surface of the core. The cam action achieved by the undulating cam faces causes the leaves to expand uniformly to center the shaft in the core. A secure grip between the chuck and the core is achieved because the outer edges of the radial walls 32 of the adapter leaf members 30 bite into the relatively soft inner surface of the paper roll core 13.

A novel core member has thus been described which adapts a conventional paper roll chuck for use with paper rolls having larger than ordinary internal diameter and which maintains the perfect centering and uniform expansion features of the chuck and at the same time securely grips the paper roll core to prevent the paper roll from slipping or coasting relative to the chuck and the shaft on which it is mounted.

By providing a supplementary adapter leaf corresponding to each chuck leaf and alining the adapter leaf with its associated chuck leaf, the built-up paper roll chuck is adapted for use with the large diameter core paper rolls.

Accordingly, perfect centering of the built-up chuck is f attained.

The ridges on the adapter chuck leaf 30 formed by the walls 32 in the indentations formed by the slots 31 are effective in preventing rotation between the adapter leaves of the built-up chuck, the chuck leaves and the paper roll. The ridges bite into the inner surface of the core, as described above, in an embossing action to slightly transform the core. In this manner the grip between the core and the roll is enhanced, effectively preventing a shift between them.

I claim as my invention:

1. A built-up expanding chuck for mounting paper rolls having large diameter cores on a shaft, the chuck including an inner tubular member adapted to be secured on relative to the inner member, said inner member and said chuck leaves having mutually engaging cam faces thereon, and means lfor moving said leaves axially relative to the inner member, a plurality of quadrant-shaped adapter chuck leaves corresponding in number to said chuck leaves and adapted to be interposed between the chuck leaves and the paper roll for engaging the paper roll core, each of said adapter chuck leaves having an arcuate outer surface, a radially extending slot opening into said outer surface, said slot having radial walls, the outer edges of said walls adapted to bite into the inner surface of the paper roll core and deform the same into said slots, a radially extending key on one of said chuck leaves adapted to engage at least one of said adapter chuck leaves for preventing relative rotation between said chuck leaves and said adapter chuck leaves, and a plurality of tension springs surrounding said adapter chuck leaves to hold the same in engagement with said chuck leaves.

2. A built-up expanding chuck for mounting paper rolls having large diameter cores on a shaft, the chuck including an inner member adapted to -be secured to the shaft, a plurality of segmental leaves concentric with said inner member and having cam means -for radially expanding them toward engagement with the paper roll, a plurality of annular segmental adapter leaves corresponding in number to said first named segmental leaves and adapted to be interposed between said leaves and the paper roll core, and locking means interposed between at least one of said segmental adapter leaves and its associated leaf -for preventing relative rotation between said leaves when the latter has been forcibly expanded into firm gripping engagement with the paper roll core, the outer surface of at least one of said adapter chuck leaves having spaced ridges with interposed indentations to provide embossing engagement between said ridges and the core incident to said forcible expansion.

3. A built-up expanding chuck having adapter chuck leaves for mounting paper rolls having large diameter cores on a shaft, said expanding chuck including an inner member telescopically mounted on and secured to the shaft and a plurality of outer leaves concentric with said inner member and expansible towards engagement with the core of the paper roll upon axial movement thereof relative to the inner member and means for moving said leaves axially relative to the inner member, said expanding adapter chuck leaves being in the form of sectors surrounding the outer leaves of said expanding chuck and adapted to be interposed between said expanding chuck and the inner base of the core of the paper roll, one of said outer leaves having a pair of spaced projections on the outer surface thereof, and a radial wall on one of said adapter chuck leaves engageable with said projections for preventing the relative rotation of said outer leaves and said adapter chuck leaves.

4. A paper roll chuck for securing core mounted paper rolls on a shaft, comprising in combination an inner member adapted to be fastened to the shaft, a plurality of axially extending leaves circumferentially surrounding said member, said leaves and said member having mutuallly engaging cam faces thereon for forcibly separating the -former from the latter upon axial movement therebetween, a plurality of angular segmental adapter leaves surrounding said first named leaves, means -for keying at least one of said adapter leaves to a corresponding leaf the shaft, a plurality of quadrant-shaped chuck leaves l concentric with said inner member and expansible towards engagement with the paper roll upon axial movement to prevent rotation of said adapter leaf thereon, and means for moving said lrst named leaves axially relative to said inner member to expand said annular segmental adapter leaves radially into firm gripping engagement with the inner surface of the paper roll core.

5. A paper roll chuck for securing core mounted paper rolls on a shaft, comprising in combination an inner member adapted to be fastened to the shaft, a plurality of axially extending segment-shaped leaves circumferentially surrounding said member, said leaves and said member having mutually engaging cam faces thereon for forcibly separating the same upon axial movement there- Ibetween, a key on one of said leaves, a plurality of annular segmental adapter leaves corresponding in number to said first named leaves and circumferentially surrounding the same, at least one of said adapter leaves having a slot for cooperating Wtih said key, a coil spring surrounding said adapter leaves and holding the same around the first named leaves, and means for moving said leaves axially relative to said inner member to expand said adapter leaves radially against the tension of said spring and into gripping engagement with the inner surface of the paper roll core.

6. A paper roll chuck for securing core mounted paper rolls on a shaft, comprising in combination an inner member telescopically mounted and fastened to the shaft, a plurality of axially extending segment-shaped leaves circumferentially `surrounding said member, said leaves and said member having mutually engaging cam faces thereon for forcibly separating the former from the latter upon axial movement therebetween, a plurality of annular segmental adapter leaves surrounding said irst named leaves, eac-h of said adapter leaves having a radially extending slot opening into the outer surface thereof, said outer surface thereby being adapted to bite into the inner surface of the paper roll core and deform the same into said slots, means for keying at least one of said adapter leaves to a corresponding leaf to prevent rotation of the same on said leaves, a coil spring surrounding said adapter leaves and holding the same around the first named leaves, and means for moving said rst named leaves axially relative to said inner member to expand said adapter leaves radially against the tension of said spring and into rm gripping engagement With the inner surface of the paper roll core.

References Cited in the file of this patent UNITED STATES PATENTS 

